CA2365091A1

CA2365091A1 - Recycling apparatuses for waste of tire, rubber, pe, pvc and lubricant oil

Info

Publication number: CA2365091A1
Application number: CA002365091A
Authority: CA
Inventors: Chun-Pao Kuo; Ching-Tsan Tsai; Kwang Victor Lo
Original assignee: Individual
Current assignee: Individual
Priority date: 2001-12-14
Filing date: 2001-12-14
Publication date: 2003-06-14

Abstract

Recycling apparatuses for waste tires, waste rubber, polyethylene, polyvinyl chloride, and lubricant oil with thermal cracking that is aimed at the recycling of waste tires and waste rubber. In operational procedures, the solid wastes are loaded into a cracking trough. The inner tank is then sealed air tight and vacuum is applied, and subjected to indirect heating. The organic solid wastes in the cracking trough are thermally cracked to cracking gases, and then cooled through heat exchangers to produce fuels and are collected in store tanks. Residual cracking gases are re-utilized for combustion and recovered heat is supplied to be a heat source for thermal cracking.
The residual solids after thermal cracking are carbon black and steel wires, which can be recycled.

Description

2 Fig. 1 is a side cross-sectional view of a cracking trough of recycling 3 apparatus for organic solid wastes in accordance with the present invention;

4 Fig. 2 is a top cross-sectional view of the cracking trough along line 2-2 in Fig.
1;
6 Fig. 3 is an enlarged view of part B of the cracking trough in accordance with 7 Fig. l;
8 Fig. 4 is an enlarged view of part C of the cracking trough in accordance with 9 Fig. 1; and Fig. S is a schematic explanatory diagram showing operating processes of the 11 recycling apparatus for organic solid wastes.

13 1. Field of the Invention 14 The present invention relates to recycling apparatuses for organic solid wastes, and more specifically to recycling apparatus, which are operated efficiently 16 and continuously to decompose waste tires, waste rubber, polyester (PE), polyvinyl 17 chloride (PVC) and lubricant oil.
18 2. Description of Related Art 19 Generally, there are two types of waste tire recycling methods:
The first method is cutting waste tires into pieces and separating the steel 21 wires, nylon and rubber. The separated rubber is then re-utilized to manufacture 22 recycled rubber. Since the recycled rubber is of inferior quality and can not be reused 23 to manufacture new tires, the value of the recycled products in not high enough to be 24 economically attractive.
The second method is mixing an appropriate ratio of catalysts with the cut 1 small pieces of the recycled waste tire under a condition of 230-500°C and double the 2 atmospheric pressure, to cause cracking and trough distillation to produce oils, carbon 3 black, and residues. Additionally, a mixture of organic gases from cracking is 4 fractionated into light oil, diesel oil, and heavy oil, etc., which are high economic valued by-products. In this second method, the waste tire is fully utilized so that the 6 second method is more economically attractive than the first method.
7 While the existing waste tire cracking technologies may be maturing, there 8 has not been practical technical demonstration towards the integrated planning of 9 industrial application. All existing cracking technology is operated on a single batch basis, i.e., both cracking and recovery of the fuel mixture are proceeded a batch at a 11 time with no continuity between each batch. Since every cracking tank is operated 12 independently, the cracking technology is hard to integrate in the recovery equipment 13 and produces a lot of problems for operation and management. Additionally, 14 practicing the cracking technology also requires more manpower and hence has a high cost of operation.
16 In addition, the cracking technologies in present use the heat generated from 17 burning oil for thermal cracking. Hot gas generated from burning is then directed to 18 peripheral pipes laced inside the cracking tank to provide indirect heating to the waste 19 tires. However, the heat transfer characteristics of the pipes are inefficient and the heat is not fully utilized.
21 During the thermal cracking, a mixture of the gases is produced and 22 exhausted to a recovery line. As cracking proceeds toward completion, the gas 23 production is reduced and is no longer discharged to the recovery line, the 24 temperature of each cracking unit may be reduced, and then the residues can be removed. However, when the cover of the cracking tank is opened, remaining gases 1 escape to the atmosphere causing not only air pollution but also affecting operators' 2 health.
3 Therefore, the present invention is raised to mitigate and/or eliminate the 4 existing problems of the cracking technology.
SUMMARY OF THE INVENTION
6 A first objective of the invention is to provide recycling apparatuses for 7 organic solid wastes such as waste tires, waste rubber, polyethylene, polyvinyl 8 chloride, and lubricant oil, wherein the recycling apparatuses are operated 9 continuously to achieve high efficiency.
A second objective of the invention is to provide recycling apparatuses for 11 organic solid wastes that have efficient heat utilization.
12 A third objective of the invention is to provide recycling apparatuses for 13 organic solid wastes that exhaust remaining gases from inner tanks to avoid ill effects 14 to operators' health.
A fourth objective of the invention is to provide recycling apparatuses for 16 organic solid wastes that prevent self ignition of cracking gases.
17 A fifth objective of the invention is to provide recycling apparatuses for 18 organic solid wastes that facilitate the thermal cracking efficiency.
19 Other objects, advantages and novel features of the invention will become more apparent from the following detailed description when taken in conjunction 21 with the accompanying drawings.

23 Recycling apparatuses for organic solid wastes such as waste tires, waste 24 rubber, polyethylene (PE), polyvinyl chloride (PVC), and lubricant oil, that the recycling apparatuses mainly comprise a combustion chamber (A), multiple cracking 1 troughs (Al,...An), and multiple pluralities of controlling valves (Vcs, Ves, Vis, and 2 Vss).
3 With reference to Figs. 1 and 2, a cracking trough (Al) is composed of a heat 4 insulation tank (1), an inner tank (2), and a top cover (3).

5 The heat insulation tank ( 1 ) is constructed in a circular shape using heat 6 durable bricks to form an inner wall thereof. A U-shaped dividing wall (11) is 7 vertically formed- along the inner wall of the heat insolating tank ( 1 ) to support the 8 inner tank (2) and construct an isolating layer (112). A groove (12) is defined in a top 9 surface of the heat insulation tank (1) for mating with the inner tank (2).
An inlet (13) and an outlet ( 14) are oppositely defined in the insulation tank ( 1 ) perpendicular to the 11 dividing wall ( 11 ) (see Fig. 2) and communicate with the isolating layer ( 112) of the 12 insulation tank ( 1 ).
13 The inner tank (2) is a circular shell mounted on the dividing wall ( 11 ) and 14 has an outer diameter smaller than an inner diameter of the heat insulation tank ( 1 ) so as to be received in the heat insulation tank ( 1 ). A circular overhang (21 ) is formed 16 laterally and outwardly from a top periphery of the inner tank (2) and has a flange (22) 17 formed on an under surface thereof to correspond to the groove ( 12) of the heat 18 insulation tank ( 1 ). Therefore, the inner tank (2) is firmly supported by the heat 19 insulation tank ( 1 ) when received inside the heat insulation tank ( 1 ).
A middle partition (24) extending laterally inside an inner space of the inner tank (2) divides the 21 inner space of the inner tank (2) into a lower compartment (241) and an upper 22 compartment (243). Multiple heating tubes (25a, 25b) are vertically secured on the 23 middle partition (24) in a radial configuration, wherein a first heating tube (25a) is at a 24 center of the upper compartment (243) and a plurality of second heating tubes (25b) are evenly distributed around the first heating tube (25a) at a half way point of the 1 radius of the inner tank (2). Each heating tube (25a, 25b) has multiple heating plates 2 (251) attached around outer peripheries of the heating tubes (25a, 25b) and multiple 3 tapered connectors (252) formed on the top of the heating plates (251).
4 With reference to Figs. 1 and 3, the top cover (3) covers the inner tank (2) and has multiple air seals (31 ) partially embedded along it's edge facing down to contact 6 with the overhang (21 ) of the inner tank (2) so as to make the inner tank (2) airtight.
7 Additionally, for each individual cracking trough (A1), the top cover (3) is fastened to 8 the inner tank (2) by screws (4).
9 With reference to Figs. 1 and 4, multiple recesses (32) are defined in the bottom face of the top cover (3) to mate with the corresponding tapered connectors 11 (252) of the heating tubes (25a, 25b). Additionally, multiple washers (253) are 12 secured inside the recesses (32) and sandwiched by the top cover (3) and the tapered 13 connectors (252) to provide an airtight effect for the heating tubes (25).
A network of 14 pipelines is communicated with the cracking trough (A 1 ) at the top cover (3), wherein the pipelines connect to the multiple pluralities of three-way recycling valves 16 (Vs 1. . . Vsn), three-way cooling valves (Vc 1. . . Vcn), pressure releasing valves 17 (Vi 1. . . Vin), and exhausting valves (Ve 1. . . Ven).
18 Now referring to Figs. 1 and 5 showing the recycling apparatus for organic 19 solid wastes in assembly, each cracking trough (A1) is connected to the multiple three-way valves (Vs, Vi, Vc, Vn). A heat supply pipe (5), a recycle pipe (6), a 21 discharge pipe (7), and exhaust pipe (8) are connected respectively in parallel as 22 shown in Fig. 5. The heat supply pipe (5) is connected to the combustion chamber (A), 23 which provides heat to the cracking troughs (Al ...An). The recycle pipe (6) is 24 connected to a heat exchanger (B), which is connected to a store tank (C) to collect condensed liquid in the heat exchanger (B) and a return pipe (9) to recycle oil gases to 1 the combustion chamber (A). The discharge pipe (7) is connected to a cooling heat 2 exchanger (D), which is connected to a vacuum pump (E). The vacuum pump (E) is 3 connected back to the combustion chamber (A). The exhaust pipe (8) is connected to 4 an air pollution controlling apparatus (F) and then to a fan (G) and a stack. (H).
In order to understand operational procedures of a plurality of the recycling 6 apparatus for organic solid wastes in assembly, a detailed illustration of Fig. 5 is 7 described as follow:
8 First, turning off all the valves of the plurality of cracking troughs (Al ...An) 9 and then removing the inner tanks (2) out from the heat insulation tank ( 1 ) to load waste tire pieces inside the inner tanks (2). Lowering the inner tanks into the heat 11 insulation tank (1) and closing the top covers (3). Opening all evacuating ends of the 12 three-way recycling valves (Vs 1. . . Vsn) to evacuate air from the inner tanks (2) until 13 the pressures in the inner tanks (2) fall below 0.05 atm. Under this low-pressure 14 condition, self ignition of gas mixtures after cracking is eliminated because of a lackof oxygen and other oxide gases such as nitrogen oxides, sulfur oxides.
Then 16 closing the evacuating ends of the three-way recycling valves (Vsl ...Vsn) and 17 opening recycling ends of the three-way recycle valves (VsI...Vsn) to reflow the 18 initial cracking gas back into the inner tanks (2). In this way, the thermal cracking rate 19 of the waste tires is increased.
Then opening gas inlet ends of the three-way cooling valves (Vc 1. . . Vcn), 21 which are connected to the cracking troughs (A1...An), and the exhausting valves 22 (Vel . ..Ven) connected to the releasing pipe (8) at the same time to adjust the flow rate 23 in balance in the cracking troughs (A 1. . . An). Additionally, turning on an air 24 controlling valve (Va) and a fuel controlling valve (Vf) of the combustion chamber (A) to adjust an suitable air/fuel ratio so as to make the air and fuel mixture burning 1 completely in the combustion chamber (A) to produce heating gas. The heating gas 2 produced from the combustion chamber (A) is channeled through the heat supply pipe 3 (5) to all heat heating tubes (25a, 25b) of the cracking troughs (A1...An) arranged in 4 parallel so that each heat dissipation tube (25) heats up the inner tank (2) indirectly.
Then, the heating gas is exhausted by the exhaust pipe (8) from the cracking troughs 6 (Al ...An) to the air pollution controlling equipment (F), and finally discharged via 7 the fan (G) and the stack (H). Therefore, after utilizing the heating gas from the 8 combustion chamber (A) to heat the cracking troughs (A 1. . . An), all polluting 9 compounds containing sulfur, carbon, nitrogen, and chloride are removed through the air pollution controlling equipment (F) from the heating gas. In compliance with air 11 emission standards, the heating gas is safe enough to be discharged into the 12 atmosphere.
13 When the heating gas from the combustion chamber (A) is directed into the 14 inner tanks (2), in order to maintain a desired cracking temperature, the three-way cooling valves (Vc 1. . . Vcn) are adjusted to open an air inlet ends to provide a suitable 16 amount of cool air to mix with the heating gas, and therefore reach the desired 17 cracking temperature. Under an appropriate temperature, the waste tires in the inner 18 tanks (2) of the cracking troughs (Al ...An) are melted into viscous fluid with low 19 fluidity, wherein thermal cracking begins and gaseous compounds are released. At this moment, the evacuating ends of the three-way recycle valves (Vsl ...Vsn) 21 connected to the inner tanks (2) are opened to allow the cracking gases from cracking 22 troughs (Al ...An) be directed through the recycle line (6) to the heat exchanger (B).
23 In the heat exchanger (B), the cracking gases are cooled, wherein oil gases containing 24 in the cracking gases are condensed into liquid and collected in the store tank (C). The condensed liquid is an oil mixture, which can be separated into valuable products 1 such as light oil, gasoline, kerosene, diesel oil, and heavy oil etc.
Remaining cracking 2 gases are incondensable and re-utilized through the return pipe (9) and directed back 3 to the combustion chamber (A).
4 During thermal cracking in the cracking troughs (A 1. . . An), as the cracking gases are produced, pressure is built up inside the inner tanks (2). The pressure inside 6 the inner tanks (2) is monitored to determine if pre-set values are reached, whereby 7 the gas inlet ends of the three-way cooling valves (Vs 1. . . Vcn), the recycling ends of 8 the three-way recycle valves (Vs 1. . . Vsn) and the exhaust valves (Ve 1. .
. Ven) are 9 opened to maintain the appropriate temperature range in the inner tanks (2).] When the cracking gases are degenerated and the pressures drops to equal or below the 11 pre-set value, then the gas inlet ends of the three-way cooling valves (Vc 1. . . Vcn) and 12 the recycling ends of the three-way recycle valves (Vs 1. . . Vsn) are opened. At the 13 same time, outlet ends of the three-way cooling valves (Vc 1. . . Vcn) and evacuating 14 ends of the three-way recycle valves (Vs 1. . . Vsn) are opened in accompaniment with starting the vacuum pumps (E) to suck out the cracking gases from the inner tanks (2) 16 to achieve a vacuum condition inside the cracking troughs (Al ...An). The evacuated 17 cracking gases are directed through the discharge pipes (7) to the cooling heat 18 exchanger (D), and then re-utilized through the return pipes (9) back to the 19 combustion chamber (A).
When the inner tanks (2) are under the vacuum condition, the air inlet ends of 21 the cooling three-way valves (Vc 1. . . Vcn) are opened so as to allow the cold air 22 flowing into the heat insulation tank ( 1 ) and the heating tubes (25) to purge air from 23 combustion chamber (A) via the exhaust pipe (8) to the air pollution controlling 24 equipment (F). At the same time, the cold air also cools the inner tanks (2). When the temperatures of the inner tanks (2) reach safe values, the pressure releasing valves I~
1 (Vi 1. . . Vin) are gradually opened to allow the pressures inside the inner tanks (2) to 2 return to the atmosphere pressure. Then, the air inlet ends of the cooling three-way 3 valves (Vc 1. . . Vcn) and the pressure releasing valves (Vi 1. . . Vin) are closed.
4 Hereafter, the top covers (3) are enabled to be detached and the inner tanks (2) are taken out from the cracking troughs (A 1. . . An). Residuum of the waste tires inside the 6 inner tanks (2) after cracking is then poured out from the inner tanks (2) and new 7 batch of the waste tires pieces is loaded into the inner tanks (2) to repeat the 8 aforementioned operational procedures.
9 When the operational procedures are completed in one of the cracking troughs (A 1 ), the cooling three-way valves (Vc 1. . . Vcn), pressure relief valves 11 (Vi 1. . . Vin), and ends of the three-way recycle valves (Vs 1. . . Vsn) to the cold air are 12 opened accordingly so as to lower the pressure and the temperature of the heat 13 insulation tanks ( 1 ) until they reach suitable values. Each cracking trough (A 1 ) is 14 operated independently to remove the residuum of the waste tires, and therefore the operational procedure of other cracking troughs (Al ...An) is not interrupted.
Hence, 16 the cracking processes of the waste tires are operated continuously. This is a fast and 17 efficient process that also requires less manpower than prior arts.
Additionally, the 18 residual solids of the waste tires after thermal cracking are carbon black and steel 19 wires, which can be recycled.
Also, the heating tubes (25) in each inner tank (2) of each cracking trough (A) 21 have multiple heat heating plates (251) installed on the outer periphery thereof so as 22 to improve the effect of heat transfer and enhance the efficiency of heat recovery and 23 reduce heat loss.
24 Additionally, the top covers (3) of all cracking troughs (A1...An) are equipped with the discharge pipes (7), heat exchanger (B), and vacuum pump (E) so that the residual cracking gases from the waste tires are completely evacuated before 2 releasing pressures and the opening the top covers (3). Therefore, residual cracking gases in the inner tanks (2) are removed to prevent polluting the environment and 4 endangering health of operators.
Even though numerous characteristics and advantages of the present 6 invention have been set forth in the foregoing description, together with details of the 7 structure and function of the invention, the disclosure is illustrative only, and changes may be made in detail, especially in matters of shape, size, and arrangement of parts 9 within the principles of the invention to the full extent indicated by the broad general meaning of the terms in which the appended claims are expressed.

Claims

The embodiment of the invention in which an exclusive property or privilege is claimed are defined as follows:

1. Recycling apparatuses for organic solid wastes such as waste tires, waste rubber, polyester, polyvinyl chloride, and lubricant oil, the recycling apparatuses adapted to operate thermal cracking continuously and comprising:
a combustion chamber (A) producing heating gases to provide heat for thermal cracking;
multiple cracking troughs (A1,...An) connecting with the combustion chamber (A) and producing cracking gases;
a heat exchanger (B) arranged next to the cracking troughs (A1...An) to condense the cracking gases;
multiple pluralities of controlling valves (Vcs, Ves, Vis, and Vss) and pipes mounted on corresponding pipes to control flow rates of cracking gases;
wherein each cracking trough (A1) connects with a heat supply pipe (5) connected to the combustion chamber (A) to provide heat to the cracking trough (A1);
a recycle pipe (6) connected to a heat exchanger (B) to collect condensed cracking gases in the heat exchanger (B); and a return pipe (9) connected with the heat exchanger (B) and recycling oil gases to the combustion chamber (A); and wherein the heating gases and the cracking gases are recycled to raise cracking effects on the organic solid waste.

2. A cracking trough (A1) adapted to be used in the recycling apparatus for organic solid wastes in claim 1, wherein the cracking trough (A1) comprises:
a heat insulation tank (1) having a dividing wall (11) vertically formed along the heat insolating tank (1);
a groove (12) defined in a top the heat insulation tank (1);
an inlet (13) and an outlet (14) defined in the insulation tank (1) to communicate with the heat supply pipe (5) and exhausting valves (Ve) respectively;
an inner tank (2) receiving the insulation tank (1) and mounted on the dividing wall (11), the inner tank (2) having:
an overhang (21) formed from the inner tank (2);
a flange (22) formed on the overhang (21) to correspond to the groove (12) of the heat insulation tank (1) so as to make the inner tank (2) firmly supported by the heat insulation tank (1) when the inner tank is received inside the heat insulation tank (1);
a middle partition (24) extending inside the inner tank (2) to divide the inner tank (2) into a lower compartment (241) and an upper compartment (243);
and multiple heating tubes (25a, 25b) vertically secured on the middle partition (24) to dissipate heat to the inner tanks (2); and a top cover (3) covering the inner tank (2) and having:
multiple air seals (31) embedded in the top cover (3) to contact with the overhang (21) of the inner tank (2) to make the inner tank (2) airtight;
multiple recesses (32) defined in the top cover (3) to mate with the heating tubes (25a, 25b); and multiple washers (253) secured inside the recesses (32) and sandwiched by the top cover (3) and the heating tubes (25a, 25b) to provide an airtight effect for the heating tubes (25).

3. Recycling apparatuses for organic solid wastes as claimed in claim 1, wherein the recycling apparatuses further comprise a cooling exchanger (D) connected back to the combustion chamber (A) and a vacuum pump (E) next to the cooling exchanger (D) to purge and recycle the cracking gases.

4. Recycling apparatuses for organic solid wastes as claimed in claim 1, wherein the recycling apparatuses further comprise an exhaust pipe (8) communicating the heating tubes (25) and an air pollution controlling equipment (F) to treat the heating gases.